Color-Redshift Relations and Photometric Redshift Estimations of Quasars in Large Sky Surveys

  title={Color-Redshift Relations and Photometric Redshift Estimations of Quasars in Large Sky Surveys},
  author={Xue-Bing Wu and Wei Zhang and Xu Zhou},
  journal={Chinese Journal of Astronomy and Astrophysics},
With a recently constructed composite quasar spectrum and the ?2 minimization technique, we describe a general method for estimating the photometric redshifts of a large sample of quasars by deriving theoretical color-redshift relations and comparing the theoretical colors with the observed ones. We estimated the photometric redshifts from the 5-band SDSS photometric data of 18678 quasars in the first major data release of SDSS and compared them with their spectroscopic redshifts. The… Expand

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